This is super helpful and accurate. I ordered one online for $115 and it came with the correct pulley installed and clocked properly.

I also pulled the alternator harness from a 1992 IDI parts truck that had factory serpentine / 3G alternator and it is completely plug and play for my 91 IDI vbelt. The fender harness, alt plugs, and tach sender plug as well as AC compressor plug are all in the harness, proper length and there is no need to splice any wires at all

 

I'll have to look into this for my 89, a few months ago I snagged a 3g alternator off of a 95 460 and pulled it with the whole harness and all thinking when the 1g goes ill have one ready to swap on or a spare for my 85 that's already been converted.

That price is hard to beat as well. Think it's 175ish locally but comes with a lifetime warranty but of course you have to reclock it, trim the front case ect which may void the warranty if they look closely.

 

may as well add this link 3G Conversion - Gary's Garagemahal (the Bullnose bible)

I'm sure many will find it handy too... I've posted it here in the past too but lots of things get lost in the static

 

I got that same alternator when I did mine a few years ago. Worked well. The biggest pain was making my own harness.

 

I wanted to write something up to save some of you the time I had to take to research everything I needed. I have a 1987 Ford F250 SuperCab 6.9L Diesel 4X4. Garbage old style Alternator/Voltage Regulator died and was looking for a replacement when I stumbled on to this post. Before this, I would run my AC on full and have my Stereo blasting (2 amps) and the best the old Alternator could do was 12.5 Volts @ 40 amps. It was pathetic. Sometimes then I selected the highest Fan speed (moving the switch all the way over); my voltage would drop to 11 volts and blow the 30amp fuse. Lower Voltage = Higher Amperage. My charging system was fried and so was I.

I used the alternator from a 1994 Ford E-150 Econoline with 4.9L V6. I had to run around to different stores because I couldn’t find all the parts at just one. Advanced Auto have the correct Alternator and I didn’t have to re-clock it. Couldn’t find the Stator connector anywhere and found that on Amazon. For the Main 4ga Cables, I crimped the ends and soldered them, then used Shrink sleeve. The Mega Fuse block studs are long enough to bolt down the fuse and put a few connections from the Starer relay on to it using the M8 nuts. I had way too many things on that Starter Relay stud.

Got it all wired up, Alt bolted in, fire the puppy up and It’s Alive! I now have 14.3V @ 800 RMP (Idle) and in running the AC on Full and Stereo blasting it only dropped to 13.7 Volts at idle. I haven’t checked the amperage yet, but I’m sure it’s doing what it’s supposed to do. Running the same test driving down the road, I had just under 14 volts constantly. What a difference and the engine compartment look cleaner without all the Voltage Reg wires. I haven’t cleaned up and dressed the wires yet because I wanted to make sure it’s all working.

Here are the parts and part numbers I used:

- Large case 3G alt with 8.25" ear spacing – Advanced Auto Part# 7761-2-6GAV 130 Amp
- 3 Wire Plug - Advanced Auto Part# PTA1025
- 1 Wire Stator Connector – Amazon - Pico 5747PT Ford Alternator Pigtail Connector
- Mega fuse (AMG) fuse holder – Napa Part# 782-1143
- 175A Mega fuse (AMG) – Napa Part# 782-1139
- Battery Cable 4 Gauge (approx. 3’ Red) Napa Part# 736108
- Cable lug ends Three 5/16" Napa Part#721133
- Cable lug end One 1/4" Napa Part#721132
- 14 Gauge Yellow wire – Auto Zone – Dorman Part # 85722
- 16 Gauge Green - Auto Zone – Dorman Part # 85731
- 5/16 Crimp Ring Lug - Blue End – For Yellow wire to connect to Starter Relay
- Wire Flex Conduit 3/4” X 10’ Black - Advanced Auto Part# 86665
- Wire Flex Conduit 1/2” X 10’ Black - Advanced Auto Part# 86664
- M8 Metric Bolt, M8 1.25 50mm (1 1/4" long if missing top mounting bolt)
- M8 Metric M8 Lock Washer – 3 (1 for the Alt Mounting, 2 for the studs on the Mega Fuse block)
- M8 Metric M8 Large “Thick” Washer - 1
- M8 Metric M8 1.25
- Shrink Sleeving – Harbor Freight - Heat-Shrink Tubing Assortment with Case, 127 Piece